Don't they have this very thing to attach camper shells to the back of trucks? That's what I'd use. I think you can get it fairly thick, meaning like 1/3 inch or something and quite industrial also..not the grand auto peel and stick foam. Oh, hey...if it is to be "permanent-ish" hows about getting the really thick 1/2 "tootsy-roll" they use to install lay-in windshields? Maybe that'd work in conjunction with another material..
